Nikolaos P. Polyzos
Vrije Universiteit Brussel
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Human Reproduction | 2011
Paul Devroey; Nikolaos P. Polyzos; Christophe Blockeel
Published data indicate a significant increase in ovarian hyperstimulation syndrome globally. The occurrence of approximately three maternal deaths per 100,000 stimulated women has been reported, and extrapolation of these figures to a global situation would give an impressive number. The syndrome can be erased by applying ovarian stimulation using the combination of GnRH antagonist with GnRH agonist to trigger ovulation. In this case, the strategy is to freeze all of the oocytes or embryos for later use.
Journal of the National Cancer Institute | 2008
Davide Mauri; Nikolaos P. Polyzos; Georgia Salanti; Nicholas Pavlidis; John P. A. Ioannidis
BACKGROUND Many systemic nonhormonal regimens have been evaluated across several hundreds of randomized trials in advanced breast cancer. We aimed to quantify the relative merits of these regimens in prolonging survival. METHODS We performed a systematic review of all trials that compared different regimens involving chemotherapy and/or targeted therapy in advanced breast cancer (1973-2007). Regimens were categorized a priori into different treatment types. We performed multiple-treatments meta-analysis and calculated hazard ratios for each treatment category relative to monotherapy with old agents (ie, regimens not including anthracyclines, anthracenediones, vinorelbine, gemcitabine, capecitabine, taxanes, marimastat, thalidomide, trastuzumab, lapatinib, or bevacizumab). RESULTS We identified 370 eligible randomized trials (54,189 patients), of which 172 (31,552 patients) compared different types of treatment. Survival data from 148 comparisons pertaining to 128 of the 172 trials (26,031 patients, 22 different types of treatment) were available for inclusion in the multiple-treatments meta-analysis. Compared with single-agent chemotherapy with old nonanthracycline drugs, anthracycline regimens achieved 22%-33% relative risk reductions in mortality (ie, hazard ratio [HR] for standard-dose anthracycline-based combination: 0.67, 95% credibility interval [CrI] 0.57-0.78). Several newer regimens achieved further benefits (eg, HR [95% CrI] 0.67 [0.55-0.81] for single-drug taxane, 0.64 [0.53-0.78] for combination of anthracyclines with taxane, 0.49 [0.37-0.67] for taxane-based combination with capecitabine or gemcitabine), and similar benefits were seen with several regimens including molecular targeted treatments. Most regimens had very similar efficacy profiles (<5% difference in HR) as first- and subsequent-line therapies. CONCLUSIONS Stepwise improvements in efficacy of chemotherapy and targeted treatments cumulatively have achieved major improvements in the survival of patients with advanced breast cancer. Many options that can be used in first and subsequent lines of therapy have comparable efficacy profiles.
BMJ | 2010
Nikolaos P. Polyzos; Ilias P. Polyzos; Apostolos Zavos; Antonis Valachis; Davide Mauri; E.G. Papanikolaou; Spyridon Tzioras; Daniel Weber; Ioannis E. Messinis
Objective To examine whether treatment of periodontal disease with scaling and root planing during pregnancy is associated with a reduction in the preterm birth rate. Design Systematic review and meta-analysis of randomised controlled trials. Data sources Cochrane Central Trials Registry, ISI Web of Science, Medline, and reference lists of relevant studies to July 2010; hand searches in key journals. Study selection Randomised controlled trials including pregnant women with documented periodontal disease randomised to either treatment with scaling and root planing or no treatment. Data extraction Data were extracted by two independent investigators, and a consensus was reached with the involvement a third. Methodological quality of the studies was assessed with the Cochrane’s risk of bias tool, and trials were considered either high or low quality. The primary outcome was preterm birth (<37 weeks). Secondary outcomes were low birthweight infants (<2500 g), spontaneous abortions/stillbirths, and overall adverse pregnancy outcome (preterm birth <37 weeks and spontaneous abortions/stillbirths). Results 11 trials (with 6558 women) were included. Five trials were considered to be of high methodological quality (low risk of bias), whereas the rest were low quality (high or unclear risk of bias). Results among low and high quality trials were consistently diverse; low quality trials supported a beneficial effect of treatment, and high quality trials provided clear evidence that no such effect exists. Among high quality studies, treatment had no significant effect on the overall rate of preterm birth (odds ratio 1.15, 95% confidence interval 0.95 to 1.40; P=0.15). Furthermore, treatment did not reduce the rate of low birthweight infants (odds ratio 1.07, 0.85 to 1.36; P=0.55), spontaneous abortions/stillbirths (0.79, 0.51 to 1.22; P=0.28), or overall adverse pregnancy outcome (preterm births <37 weeks and spontaneous abortions/stillbirths) (1.09, 0.91 to 1.30; P=0.34). Conclusion Treatment of periodontal disease with scaling and root planing cannot be considered to be an efficient way of reducing the incidence of preterm birth. Women may be advised to have periodical dental examinations during pregnancy to test their dental status and may have treatment for periodontal disease. However, they should be told that such treatment during pregnancy is unlikely to reduce the risk of preterm birth or low birthweight infants.
American Journal of Obstetrics and Gynecology | 2009
Nikolaos P. Polyzos; Ilias P. Polyzos; Davide Mauri; Spyridon Tzioras; Maria Tsappi; Ivan Cortinovis; Giovanni Casazza
We conducted a metaanalysis of randomized controlled trials to determine whether periodontal disease treatment with scaling and/or root planing during pregnancy may reduce preterm birth (PTB) or low birthweight (LBW) infant incidence. Treatment resulted in significantly lower PTB (odds ratio [OR], 0.55; 95% confidence interval [CI], 0.35-0.86; P = .008) and borderline significantly lower LBW (OR, 0.48; 95% CI, 0.23-1.00; P = .049), whereas no difference was found for spontaneous abortion/stillbirth (OR, 0.73; 95% CI, 0.41-1.31; P = .292). Subgroup analysis suggested significant effect of treatment in the absence of history of PTB or LBW (OR, 0.48; 95% CI, 0.29-0.77; P = .003) and less severe periodontal disease as defined by probing depth (OR, 0.49; 95% CI, 0.28-0.87; P = .014) or bleeding on probing site (OR, 0.37; 95% CI, 0.14-0.95; P = .04). If ongoing large and well-designed randomized trials support our results, we might need to reassess current practice or at least be cautious prior to rejecting treatment of periodontal disease with scaling and/or root planing during pregnancy.
Human Reproduction | 2013
Peter Humaidan; Nikolaos P. Polyzos; Birgit Alsbjerg; Karin Erb; Aage Mikkelsen; Helle Olesen Elbaek; E.G. Papanikolaou; Claus Yding Andersen
STUDY QUESTION Does a GnRH agonist (GnRHa) trigger followed by a bolus of 1.500 IU hCG in a group of patients at risk of ovarian hyperstimulation syndrome (OHSS) reduce the OHSS incidence compared with hCG trigger? SUMMARY ANSWER A GnRHa trigger followed by early luteal hCG support with one bolus of 1.500 IU hCG appears to reduce OHSS in patients at risk of OHSS; however, in a low-risk group a second bolus of 1.500 IU hCG induced two cases of late onset OHSS. WHAT IS KNOWN ALREADY A GnRHa trigger is an alternative to hCG in GnRH antagonist co-treated cycles. STUDY DESIGN, SIZE, DURATION Two RCTs were performed in four Danish IVF units. A total of 446 patients were assessed for eligibility and 390 patients were enrolled in the study from January 2009 until December 2011. The primary outcome of the study was OHSS incidence in the group at risk of OHSS. PARTICIPANTS/MATERIALS, SETTING, METHODS Patients received a fixed dose of recombinant human FSH for the first 4 days. On the day of triggering, patients were assessed for their risk of OHSS based on the total number of follicles ≥11 mm diameter, and were classified as being at risk of OHSS when the total number of follicles ≥11 mm was between 15 and 25 and at low risk of OHSS when the total number of follicles ≥11 mm was ≤14. Two separate randomization lists were used for each of the OHSS risk groups. Women at risk of OHSS were allocated (RCT 1) to either: Group A (n = 60), ovulation triggering with a bolus of 0.5 mg buserelin (GnRHa) s.c. followed by a single bolus of 1.500 IU hCG s.c. after the oocyte retrieval-or: Group B (n = 58): 5.000 IU hCG. Similarly, women at low risk of OHSS were allocated (RCT 2) to receive either: Group C (n = 125), a bolus of 0.5 mg buserelin s.c., followed by a bolus of 1.500 IU hCG s.c. after oocyte retrieval and a second bolus of 1.500 IU hCG on the day of oocyte retrieval +5-or: Group D (n = 141), 5.000 IU hCG. Groups C and D were included in order to obtain preliminary data. MAIN RESULTS AND THE ROLE OF CHANCE In women at risk of OHSS (RCT 1) (15-25 follicles) no OHSS case was seen in Group A (GnRHa trigger and one bolus of 1.500 IU hCG), whereas two cases of moderate late-onset OHSS occurred in group B (3.4%), (P = 0.24). In contrast, in women at a low risk of OHSS (RCT 2) (≤14 follicles) two cases of late-onset OHSS occurred in Group C (GnRHa trigger and two boluses of 1.500 IU hCG), whereas no OHSS case was encountered in Group D (P = 0.22). LIMITATIONS, REASONS FOR CAUTION Although the first RCT was powered to include 168 patients at risk of OHSS (15-25 follicles ≥11 mm) randomized to either GnRHa trigger or hCG trigger, the trial was prematurely discontinued when a total of 118 patients at risk of OHSS were randomized. In addition the second RCT in the OHSS low-risk group was designed as a feasibility study to assess the incidence of OHSS after GnRHa trigger and dual hCG administration versus 5.000 IU hCG. No power calculation was performed for this trial. In addition, there was a lack of blinding in the RCTs. WIDER IMPLICATIONS OF THE FINDINGS Although a non-significant result, one bolus of 1.500 IU hCG after GnRHa trigger tended to reduce the OHSS rate in patients with 15-25 follicles ≥11 mm as well as secure the ongoing pregnancy rate. In contrast, in patients at low risk of OHSS the administration of two boluses of 1.500 IU hCG after GnRHa trigger should be avoided as it may induce OHSS.
Obstetrical & Gynecological Survey | 2007
Nikolaos P. Polyzos; Davide Mauri; Maria Tsappi; Spyridon Tzioras; Konstantinos Kamposioras; Ivan Cortinovis; Giovanni Casazza
The effect of combined vitamin C and E supplementation during pregnancy on the prevention of preeclampsia and major adverse infant outcomes has been reviewed. We searched MEDLINE and the Central Library of Controlled Trials of the Cochrane Library through August 2006 for relevant clinical trials. Interstudy heterogeneity was evaluated using the &khgr;2 statistic (Q statistic) test. Pooled relative risks (RRs) and 95% confidence intervals (CIs) were calculated with a fixed or random-effects model as appropriate. Four trials that collectively randomized 4680 pregnant women to either the combination of vitamin C and vitamin E or placebo were included in the analysis. There were no significant differences between the vitamin and placebo groups in the risk of preeclampsia, 11% versus 11.4%, RR 0.97 (95% CI 0.82–1.13), fetal or neonatal loss, 2.6% versus 2.3%, RR 1.10 (95% CI 0.78–1.57), or small for gestational age (SGA) infant, 20.6% versus 20%, RR 0.94 (95% CI 0.74–1.19). Although there was a higher risk for preterm birth in the vitamin group, 19.5% versus 18%, RR 1.07 (95% CI 0.96–1.20), this finding was not significant. Combined vitamin C and E supplementation during pregnancy does not reduce the risk of preeclampsia, fetal or neonatal loss, small for gestational age infant, or preterm birth. Such supplementation should be discouraged unless solid supporting data from randomized trials become available. Target Audience: Obstetricians & Gynecologists, Family Physicians Learning Objectives: After completion of this article, the reader should be able to recall that many methods have been used to prevent preeclampsia, state that increased oxidative stress has been postulated and many trials have used antioxidants to prevent the disease, and explain that MEDLINE analysis of the literature questions the use of vitamin C and E supplements.
Human Reproduction | 2012
Nikolaos P. Polyzos; Christophe Blockeel; W. Verpoest; M. De Vos; D. Stoop; Veerle Vloeberghs; Michel Camus; Paul Devroey; Herman Tournaye
STUDY QUESTION What is the effect of natural cycle IVF in women with poor ovarian response according to the new ESHRE definition for poor ovarian responders: the Bologna criteria? SUMMARY ANSWER Although natural cycle IVF is a promising treatment option for normal responders, poor ovarian responders, as described by the Bologna criteria, have a very poor prognosis and do not appear to experience substantial benefits with natural cycle IVF. WHAT IS KNOWN ALREADY Previous trials have shown that natural cycle IVF is an effective treatment for the general infertile population and might be an option for poor ovarian responders. However, none of the trials have examined the effect of natural cycle IVF in poor responders according to the Bologna criteria, the newly introduced definition by the ESHRE Working Group on Poor Ovarian Response Definition. In this trial, we examined the effect of natural cycle IVF in poor ovarian responders fulfilling the Bologna criteria. STUDY DESIGN, SIZE, DURATION In this retrospective cohort trial, 164 consecutive patients, undergoing 469 natural cycle IVFs between 2008 and 2011 were included. Patients were stratified as poor and normal responders: 136 (390 cycles) were poor ovarian responders according to the Bologna criteria, whereas 28 women (79 treatment cycles) did not fulfil the criteria and were considered as normal responders. PARTICIPANTS/MATERIALS, SETTING, METHODS All patients were monitored with hormonal analysis and ultrasound scan every second day, from Day 7 or 8 of the cycle onwards. When a follicle of >16 mm was observed, ovulation was triggered with 5000 IU of i.m. hCG and oocyte retrieval was performed 32 h later. MAIN RESULTS AND THE ROLE OF CHANCE Live birth rates in poor responders according to the Bologna criteria were significantly lower compared with the control group of women; the live birth rate per cycle was 2.6 versus 8.9%, P = 0.006 and the live birth rate per treated patient was 7.4 versus 25%, P = 0.005. In poor responders according to the Bologna criteria, live birth rates were consistently low and did not differ among different age groups (≤ 35 years, 36-39 years and ≥ 40 years), with a range from 6.8 to 7.9%. LIMITATIONS, REASONS FOR CAUTION A limitation of our analysis is its retrospective design; however, taking into account that we included only consecutive patients treated with exactly the same protocol, the likelihood of selection bias might be considerably limited. In addition, the control group in our study refers to women of younger age and therefore the promising results among patients who did not fulfil the Bologna criteria apply only to women of younger age. WIDER IMPLICATIONS OF THE FINDINGS Our trial suggests that although natural cycle IVF is a promising treatment option for younger normal responders, its potential is very limited to poor ovarian responders as described by the Bologna criteria, irrespective of patients age. This highlights the very poor prognosis of these women and therefore the urgent need for future trials to examine the effect of ovarian stimulation protocols in women with poor ovarian response as described by the Bologna criteria. STUDY FUNDING/COMPETING INTEREST(S) No funding was used. There are no competing interests to declare.
Cancer Treatment Reviews | 2010
Davide Mauri; Konstantinos Kamposioras; Lamprini Tsali; Magdalini Bristianou; Antonis Valachis; Ioanna Karathanasi; Christos Georgiou; Nikolaos P. Polyzos
BACKGROUND Taxanes have been extensively tested in patients with advanced breast cancer, but it is unclear whether their weekly use might offer any benefits against standard every three weeks administration. We therefore performed a meta-analysis of randomized controlled trials that compared weekly and every three weeks taxanes regimens in advanced breast cancer. METHODS The endpoints that we assessed were objective response rate, progression free survival (PFS) and overall survival. Efficacy data for paclitaxel and docetaxel were separately analyzed. Trials were located through PubMed and Cochrane Library searches and abstracts of major international conferences. RESULTS Omicronbjective response rate was notably better when paclitaxel was used as every three weeks regimen (7 studies, 1772 patients, fixed effect model pooled RR 1.20 95%CI 1.08-1.32 p<0.001). No difference were found for PFS (6 studies, 1610 patients, random effect model HR 1.02, 95%CI 0.81-1.30 p=0.860); while OS was statistically higher among patients receiving weekly paclitaxel (5 studies, 1471 patients, fixed effect model pooled HR 0.78, 95%CI 0.67-0.89 p=0.001). No differences were observed for the weekly compared to the every three weeks use of docetaxel either for objective response, PFS and OS. Overall, the incidence of serious adverse events, neutropenia, neutropenic fever, and peripheral neuropathy were significantly lower in weekly taxanes schedules. The incidence of nail changes and epiphora were significantly lower in the every three weeks docetaxel regimens. CONCLUSIONS Use of paclitaxel in weekly regimen give overall survival advantages compared with the standard every three weeks regimen. The observed survival benefit does not seem to stem from an increased potency of the drug with weekly regimens. The use of weekly paclitaxel regimens is therefore recommended for the treatment of locally advanced/metastatic breast cancer.
The Breast | 2011
Antonis Valachis; Davide Mauri; Nikolaos P. Polyzos; Grigoris Chlouverakis; D. Mavroudis; V. Georgoulias
PURPOSE To perform a meta-analysis in order to quantify the actual cumulative randomized evidence for the benefit and toxicity of trastuzumab combined with neoadjuvant chemotherapy in HER2-positive breast cancer. METHODS Potentially eligible trials were located through PubMed and Cochrane Library searches and abstracts of major international conferences. The endpoints that we assessed were pathologic complete response (pCR) rate, breast-conserving surgery (BCS) rate and toxicity. RESULTS Five trials were identified with 515 eligible patients. The probability to achieve pCR was higher for the trastuzumab plus chemotherapy arm (RR 1.85, 95% CI: 1.39-2.46; p-value < 0.001). No significant difference in terms of breast-conserving surgery between the two treatment arms was observed (OR: 0.98, 95% CI: 0.80-1.19, p-value = 0.82). Regarding toxicity, the addition of trastuzumab did not increase the incidence of neutropenia, neutropenic fever, and cardiac adverse events. CONCLUSION The addition of trastuzumab in HER2-positive breast cancer in the neoadjuvant setting improves the probability of achieving higher pCR with no additional toxicity. Based on the available evidence, the use of trastuzumab combined with neoadjuvant chemothetherapy in patients with HER2-positive breast cancer seems to offer substantial benefit in terms of pCR.
Obstetrical & Gynecological Survey | 2010
Antonis Valachis; Lamprini Tsali; Lorenzo L. Pesce; Nikolaos P. Polyzos; Charalambos Dimitriadis; Konstantinos Tsalis; Davide Mauri
Background: An increased number of women are expected to conceive after the diagnosis of early breast cancer. Most physicians recommend that pregnancy be delayed by 2 to 3 years after diagnosis of early breast cancer, but this recommendation is based on data from trials with small patient cohorts. Furthermore, a healthy mother effect (HME) selection bias may be operative in most of these studies, because women undergoing childbearing after treatment were healthier when compared with the control group. Aim: To perform a systematic review and meta-analysis of published trials corrected for HME bias so as to assess the effect of pregnancy (at least 10 months after diagnosis) versus no pregnancy on overall survival of primary breast cancer patients less than 45 years. Methods: We searched MEDLINE and Thomson Reuters (ISI) Web of Knowledge for eligible studies. From each study we extracted the relative hazard ratio or, if not provided, all the necessary data to impute it. In cases where the duration from diagnosis to pregnancy was not reported, we extracted relevant data to estimate it. Results: Our electronic search strategy yielded 1623 hits pertaining to 20 potentially eligible studies involving 49,370 premenopausal breast cancer patients. Ten studies were eligible after considering HME potential bias in matching controls. Among these, 9 studies (pregnant 1089, matched-controls 13051) contained data appropriate for analysis. Overall survival was statistically higher among patients who became pregnant compared to controls: fixed effect model estimated pooled hazard ratio for death 0.51 (95% confidence interval: 0.42–0.62). No study heterogeneity was observed: Q = 10.4, P = 0.17; I2 = 48%. Conclusion: The pooled available evidence indicates that in early breast cancer patients, pregnancy that occurs at least 10 months after diagnosis does not jeopardize prognosis and may actually confer significant survival benefit. Target Audience: Obstetricians & Gynecologists, Family Physicians Learning Objectives: After completing this CME activity, physicians should be better able to assess the effect pregnancy has on long-term survival in primary breast cancer patients under age 45; counsel patients on the safety of pregnancy after breast cancer diagnosis and treatment; and interpret how pregnancy may be associated with improved breast cancer survival.